All three of the above are employed on websites as a means of communication or helping with communication.

A directory, is traditionally a list of names and addresses stored in alphabetical order. Details can be either business or personal. Internet directories are stored electronically on servers and are very useful for finding business information or to help locate a service that you require. Unlike the telephone directory, online directories can be quite specialised and many only relate to a certain topic or field such as computing. There are literately hundreds of thousands of directories on the Internet covering almost every  field of interest. The information contained is usually very useful as it will be specific, such as a directory of all holiday camp sites in France or a list of all  estate  agents in a particular area.  One of the problems with directories is that they can  become obsolete very quickly and many are now out of date. When using a directory try to locate one that looks like it is actively being updated. Paid directories normally contain the most up to date information as  when the fee becomes renewable, the business owner will discontinue if he is no longer trading or renew and provide the most up to date information.

 
Most directories follow a similar format and will provide you with a variety of ways of searching the database. Details are stored in categories and then once you have chosen a category, the  information is usually presented alphabetically. However, some directories  will offer a premium listing service, whereby on payment of a fee ( or higher fee ) your listing can be pushed further towards to the top of the page. Internet directories tend to include business details such as address telephone and fax numbers and a brief synopsis of what the company has  to offer. Most will also include a hyperlink, so you can jump straight to that companies website and view their details.

 
Internet Blogs are a relatively new idea and are now immensely popular. Most are written on an individual , informal basis, almost in the style of a diary and then can be very  entertaining. They are basically mini websites which are used for a variety of uses, from virtual soap boxes, where people can let of steam or comment on their daily activities. Most cooperate websites now include a blog as they are seen as a means of keeping customers up to date with product developments or company information. There are over  120 million blogs in existence and that number is growing on a daily basis . Most  bloggers have found that in the must inane content can become popular and some blogs have a following of thousands who avidly log on every day to keep up with information and events One advantage of the blog over a normal diary is that it allows interaction from the reader,. If you don't like some of the comments made on a blog, you are free to make a reply. However, most blogs will allow the operator to edit out and delete entries that they they don't themselves like. 

Forums have been in existence a while longer than blogs and many websites have them to allow persons to  obtain information and swap opinions or simply ask for help on various topics usually related to the theme of the website. Forums can be great places to find hard to uncover information such as reviews of hotels or holiday destinations or to help uncover technical information related to products.  Many computer uses have found forums invaluable when having to deal with virus problems for example. 

Some websites actively encourage the use of forums  to discuss and debate issues and some of the " threads" can run in to thousands of comments & replies. To  post a question  or view a forum, you normally have to join, this is to prevent spamming and so as a moderator can view your posts. Some forums operate almost as chat rooms and are almost "live", these can we quite entertaining especially if they are related to a live event. Online forums can be relatively helpful although unless organised correctly, they can prove difficult to navigate and some of the information provided may not be as accurate as your require. However, they provide a valuable referencing point for information and by reading a  number, you can take a view on the information on offer.

 
Forums which are open only to members of an organisation tend to be the most helpful as the topics cover usually only relate to the activities of the organisation to which all members share a common interest.